Fluid path set with turbulent mixing chamber, back flow compensator

ABSTRACT

A fluid path set includes a first fluid line having a proximal end fluidly connectable to a source of a first fluid and a second fluid line having a proximal end fluidly connectable to a source of a second fluid. A flow mixing device is in fluid communication with distal ends of the first and second fluid lines. The flow mixing device includes a housing, a first fluid port provided for receiving the first fluid, and a second fluid port for receiving the second fluid. A mixing chamber is disposed within the housing and is in fluid communication with the first and second fluid ports. A third fluid port in fluid communication with the mixing chamber for discharging a mixed solution of the first and second fluids. A turbulent flow inducing member is disposed within the mixing chamber for promoting turbulent mixing of the first and second fluids.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Divisional Application of U.S. Ser. No.13/799,426, filed Mar. 13, 2013, now U.S. Pat. No. 9,555,379, thedisclosure of which is incorporated herein in its entirety.

BACKGROUND OF THE INVENTION

Field of the Invention

The invention described herein relates to medical fluid deliveryapplications and, particularly, to a system for the delivery of one ormore medical fluids to a patient using a fluid path set with a turbulentmixing chamber, backflow compensator, and/or air bubble trap.

Description of Related Art

In many medical diagnostic and therapeutic procedures, a medicalpractitioner, such as a physician, injects a patient with a fluid. Inrecent years, a number of injector-actuated syringes and poweredinjectors for pressurized injection of fluids, such as contrast solution(often referred to simply as “contrast”), have been developed for use inprocedures such as angiography, computed tomography (CT), ultrasound,and NMR/MRI. In general, these powered injectors are designed to delivera preset amount of contrast at a preset flow rate.

Angiography is used in the detection and treatment of abnormalities orrestrictions in blood vessels. In an angiographic procedure, aradiographic image of a vascular structure is obtained through the useof a radiographic contrast fluid which is injected through a catheter.The vascular structures in fluid connection with the vein or artery inwhich the contrast is injected are filled with contrast. X-rays passingthrough the region of interest are absorbed by the contrast, causing aradiographic outline or image of vascular structures containing thecontrast. The resulting images can be displayed on, for example, amonitor and recorded.

In a typical angiographic procedure, the medical practitioner places acardiac catheter into a vein or artery. The catheter is connected toeither a manual or to an automatic contrast injection mechanism. Atypical manual contrast injection mechanism includes a syringe in fluidconnection with a catheter connection. The fluid path also includes, forexample, a source of contrast, a source of flushing fluid, typicallysaline, and a pressure transducer to measure patient blood pressure. Ina typical system, the source of contrast is connected to the fluid pathvia a valve, for example, a three-way stopcock. The source of saline andthe pressure transducer may also be connected to the fluid path viaadditional valves, again such as stopcocks. The operator of the manualcontrast injection mechanism controls the syringe and each of the valvesto draw saline or contrast into the syringe and to inject the contrastor saline into the patient through the catheter connection.

Automatic contrast injection mechanisms typically include a syringeconnected to one or more powered injectors having, for example, apowered linear actuator. Typically, an operator enters settings into anelectronic control system of the powered injector for a fixed volume ofcontrast and saline, and a fixed rate of injection for each. Automaticcontrast injection mechanisms provide improved control over manualapparatus where successful use of such manual devices is dependent onthe skill of the medical practitioner operating the device. As in amanual system, the fluid path from the automatic contrast injectionmechanism to the patient includes, for example, a source of contrast, asource of flushing fluid, typically saline, and a pressure transducer tomeasure patient blood pressure. The source of contrast is connected tothe fluid path via a valve, for example, a three-way stopcock. Thesource of saline and the pressure transducer may also be connected tothe fluid path via additional valves, again such as stopcocks.

When the contrast and the flushing fluid are injected, it is desirablefor the two fluids to be mixed well before injection into the patient.However, because the contrast and the flushing fluid typically havedifferent specific gravity and viscosity, the two solutions may not bethoroughly mixed using a known mixing valve, such as a T- or Y-shapedjoint, or a three-way stopcock. As a result, when the contrast and theflushing fluid are not mixed properly, the resulting image taken by afluoroscopic imaging apparatus may be uneven, thereby making itdifficult to image the blood vessel clearly. Within the prior art,International Application Publication No. WO 2011/125303 discloses amixing device for mixing two kinds of fluids. The mixing device includesa first inflow opening and a second inflow opening that is tangential tothe first inflow opening to generate a swirling flow as the first andsecond fluids come into contact. The mixing chamber has a conical shapethat is continuously narrowed to an outlet opening. However, existingsolutions are often not adequate in promoting thorough mixing of thefluids when small amounts of contrast and flushing solution areintroduced and/or when the injection duration is short. Additionally,such existing mixing devices do not compensate for backflow of thecontrast or the flushing fluid.

An additional problem with the known multi-fluid injectors is that fluidbackflow occurs in injections where a viscous first fluid is injected ata higher ratio than a less viscous second fluid. In such a scenario,before a uniform fluid flow is established, the fluid pressure of themore viscous first fluid that is injected at a higher ratio acts againstthe fluid pressure of the less viscous second fluid that is injected ata lower ratio to force the second fluid to reverse the desired directionof flow. After injection, pressures equalize, and the fluid injectionsystem achieves a steady state operation where first and secondinjection fluids are injected at a desired ratio. However, in smallvolume injections, steady state operation cannot be achieved prior tothe completion of the injection process and the total volume of firstand second fluids being delivered. Thus, even though a desired ratio offirst and second fluids may be 80% first injection fluid to 20% secondinjection fluid, the actual ratio due to backflow of the first fluid maybe higher. This problem is further compounded with an increase ininjection pressure. Utilizing check valves downstream of the syringescontaining the first and second injection fluids only preventscontamination of the syringes from the backflow and does not address theaccuracy of the final mixture ratio.

While manual and automated injectors are known in the medical field,improved fluid delivery systems having a fluid path that promotesturbulent mixing of two or more fluids introduced into a mixing chambercontinue to be in demand in the medical field. Additionally, improvedfluid transfer sets having a fluid path with a mixing device adapted forthorough fluid mixing are also desired in the medical field. Moreover,the medical field continues to demand improved medical devices andsystems used to supply fluids to patients during medical procedures suchas angiography, computed tomography, ultrasound, and NMR/MRI.

SUMMARY OF THE INVENTION

While various embodiments of a flow mixing device are described indetail herein, one embodiment may include a housing having a proximalend opposite a distal end, a first fluid port provided at the proximalend of the housing for receiving a first injection fluid, and a secondfluid port provided at the proximal end of the housing for receiving asecond injection fluid. A mixing chamber may be disposed within thehousing between the proximal and distal ends, the mixing chamber beingin fluid communication with the first and second fluid ports for mixingthe first and second injection fluids. A third fluid port may beprovided at the distal end of the housing and in fluid communicationwith the mixing chamber for discharging a mixed solution of the firstand second injection fluids. A turbulent flow inducing member may bedisposed within the mixing chamber for promoting turbulent mixing of thefirst and second injection fluids. The flow mixing device may include athird fluid port for receiving a third injection fluid. The first fluidport and the second fluid port may be substantially parallel with alongitudinal axis of the housing. The first fluid port and the secondfluid port may be radially offset from a longitudinal axis of thehousing.

In accordance with another embodiment, the turbulent flow inducingmember may include a flow dispersion device having at least onedeflection member extending over at least a portion of one of the firstand second fluid ports for deflecting the fluid flow of the firstinjection fluid or the second injection fluid from a substantiallylongitudinal direction to a direction having a radial component. Theturbulent flow inducing member may include two deflection members,wherein the first deflection member extends over at least a portion ofthe first fluid port for deflecting the first injection fluid radiallyoutward with respect to a longitudinal axis of the mixing chamber, andwherein the second deflection member extends over at least a portion ofthe second fluid port for deflecting the second injection fluid radiallyoutward with respect to the longitudinal axis of the mixing chamber.

In accordance with another embodiment, the turbulent flow inducingmember may include at least one turbine wheel having a plurality ofrotating blades oriented substantially perpendicular to a direction offluid flow through the mixing chamber, the at least one turbine wheelbeing rotatable with respect to a longitudinal axis of the mixingchamber for scattering the first and second injection fluids within themixing chamber.

In accordance with another embodiment, the turbulent flow inducingmember may include a plurality of mixing balls having a diameter largerthan a diameter of a smallest of the first, second, and third fluidports, and wherein the mixing balls are agitated within the mixingchamber by the first and second injection fluids.

In accordance with another embodiment, the turbulent flow inducingmember may include a porous filter having a plurality of open cellelements disposed within at least a portion of the mixing chamber.

In accordance with another embodiment, the turbulent flow inducingmember may include a disc disposed across a portion of the mixingchamber in a radial direction, the disc having a plurality of recessesextending radially inward from an outer circumference of the disc and atleast one opening extending through a central portion of the disc.

In accordance with another embodiment, the turbulent flow inducingmember may include a tubular insert fixed within the mixing chamber andat least one hydrofoil element extending across an interior of thetubular insert substantially parallel to a direction of fluid flowthrough the mixing chamber. The at least one hydrofoil element may havea leading edge oriented toward the proximate end, a trailing edgeoriented toward the distal end, an upper chord extending between theleading edge and the trailing edge, and a lower chord extending betweenthe leading edge and the trailing edge opposing the upper chord.

In accordance with another embodiment, the turbulent flow inducingmember may include a plurality of tubular flow dispersion members fixedrelative to the housing to define the mixing chamber, each of theplurality of flow dispersion members having a plurality of wingsextending radially inward from an interior sidewall of the flowdispersion members. The plurality of wings may be spaced apart at equalintervals around the inner circumference of each flow dispersion member,and wherein adjacent flow dispersion members are radially aligned suchthat the plurality of wings of one flow dispersion member are angularlyoffset with regard to the plurality of wings of the other flowdispersion member.

In accordance with another embodiment, the turbulent flow inducingmember may include two sinusoidal fluid paths extending through themixing chamber, and wherein the two sinusoidal paths intersect at aplurality of intersection points within the mixing chamber.

In another embodiment, the housing may have a first portion and a secondportion joined together at a seam extending around an outer perimeter ofthe housing between the proximal and distal ends. The seam may include aprojection provided on one of the first portion and the second portionand a corresponding groove on the other of the first portion and thesecond portion for receiving the projection within the groove. Themixing chamber may have a spiral sidewall.

In accordance with another embodiment, the turbulent flow inducingmember may include a first arcuate tube in fluid communication with thefirst fluid port and a second arcuate tube in fluid communication withthe second fluid port, wherein the first and second arcuate tubes arecurved radially inward toward a central axis of the mixing chamber, andwherein fluid mixing at a juncture between the first and second arcuatetubes is influenced by a Coanda effect.

In a further embodiment, a fluid path set may have a first fluid linehaving a proximal end and a distal end, where the proximal end of thefirst fluid line is fluidly connectable to a source of a first injectionfluid. The fluid path set may also include a second fluid line having aproximal end and a distal end, where the proximal end of the secondfluid line is fluidly connectable to a source of a second injectionfluid. A flow mixing device may be in fluid communication with thedistal ends of the first and second fluid lines at a proximal end of theflow mixing device. The flow mixing device may include a housing havinga proximal end opposite a distal end, a first fluid port provided at theproximal end of the housing for receiving a first injection fluid, and asecond fluid port provided at the proximal end of the housing forreceiving a second injection fluid. A mixing chamber may be disposedwithin the housing between the proximal and distal ends, the mixingchamber being in fluid communication with the first and second fluidports for mixing the first and second injection fluids. A third fluidport may be provided at the distal end of the housing and in fluidcommunication with the mixing chamber for discharging a mixed solutionof the first and second injection fluids. A turbulent flow inducingmember may be disposed within the mixing chamber for promoting turbulentmixing of the first and second injection fluids. The flow mixing devicemay include a third fluid port for receiving a third injection fluid.

In accordance with another embodiment of the fluid path set, theturbulent flow inducing member may include a flow dispersion devicehaving at least one deflection member extending over at least a portionof one of the first and second fluid ports for deflecting the fluid flowof the first injection fluid or the second injection fluid from asubstantially longitudinal direction to a direction having a radialcomponent. The turbulent flow inducing member may include two deflectionmembers, wherein the first deflection member extends over at least aportion of the first fluid port for deflecting the first injection fluidradially outward with respect to a longitudinal axis of the mixingchamber, and wherein the second deflection member extends over at leasta portion of the second fluid port for deflecting the second injectionfluid radially outward with respect to the longitudinal axis of themixing chamber.

In accordance with another embodiment of the fluid path set, theturbulent flow inducing member may include at least one turbine wheelhaving a plurality of rotating blades oriented substantiallyperpendicular to a direction of fluid flow through the mixing chamber,the at least one turbine wheel being rotatable with respect to alongitudinal axis of the mixing chamber for scattering the first andsecond injection fluids within the mixing chamber.

In accordance with another embodiment of the fluid path set, theturbulent flow inducing member may include a plurality of mixing ballshaving a diameter larger than a diameter of a smallest of the first,second, and third fluid ports, and wherein the mixing balls are agitatedwithin the mixing chamber by the first and second injection fluids.

In accordance with another embodiment of the fluid path set, theturbulent flow inducing member may include a porous filter having aplurality of open cell elements disposed within at least a portion ofthe mixing chamber.

In accordance with another embodiment of the fluid path set, theturbulent flow inducing member may include a disc disposed across aportion of the mixing chamber in a radial direction, the disc having aplurality of recesses extending radially inward from an outercircumference of the disc and at least one opening extending through acentral portion of the disc.

In accordance with another embodiment of the fluid path set, theturbulent flow inducing member may include a tubular insert fixed withinthe mixing chamber and at least one hydrofoil element extending acrossan interior of the tubular insert substantially parallel to a directionof fluid flow through the mixing chamber. The at least one hydrofoilelement may have a leading edge oriented toward the proximate end, atrailing edge oriented toward the distal end, an upper chord extendingbetween the leading edge and the trailing edge, and a lower chordextending between the leading edge and the trailing edge opposing theupper chord.

In accordance with another embodiment of the fluid path set, theturbulent flow inducing member may include a plurality of tubular flowdispersion members fixed relative to the housing to define the mixingchamber, each of the plurality of flow dispersion members having aplurality of wings extending radially inward from an interior sidewallof the flow dispersion members. The plurality of wings may be spacedapart at equal intervals around the inner circumference of each flowdispersion member, and wherein adjacent flow dispersion members areradially aligned such that the plurality of wings of one flow dispersionmember are angularly offset with regard to the plurality of wings of theother flow dispersion member.

In accordance with another embodiment, the turbulent flow inducingmember may include two sinusoidal fluid paths extending through themixing chamber, and wherein the two sinusoidal paths intersect at aplurality of intersection points within the mixing chamber.

In another embodiment of the fluid path set, the housing of the fluidmixing device may have a first portion and a second portion joinedtogether at a seam extending around an outer perimeter of the housingbetween the proximal and distal ends. The seam may include a projectionprovided on one of the first portion and the second portion and acorresponding groove on the other of the first portion and the secondportion for receiving the projection within the groove. The mixingchamber may have a spiral sidewall.

In accordance with another embodiment of the fluid path set, theturbulent flow inducing member may include a first arcuate tube in fluidcommunication with the first fluid port and a second arcuate tube influid communication with the second fluid port, wherein the first andsecond arcuate tubes are curved radially inward toward a central axis ofthe mixing chamber, and wherein fluid mixing at a juncture between thefirst and second arcuate tubes is influenced by a Coanda effect.

In a further embodiment, a method of mixing a drug solution may includethe steps of delivering a first injection fluid to a flow mixing device,delivering a second injection fluid to the flow mixing device, mixingthe first and second injection fluids inside a mixing chamber of theflow mixing device, and delivering a mixed solution of the first andsecond injection fluids from the flow mixing device. The mixing chamberof the flow mixing device may include a turbulent flow inducing memberfor promoting turbulent mixing of the first and second injection fluids.

In accordance with a further embodiment, a method for capacitance volumecorrection in a multi-fluid delivery system may include pressurizing afirst expandable body having a first injection fluid by reducing thevolume in the first expandable body with movement of a firstpressurizing element and pressurizing a second expandable body having asecond injection fluid by reducing the volume in the second expandablebody with movement of a second pressurizing element. The method mayfurther include controlling an acceleration of the first pressurizingelement relative to the acceleration of the second pressurizing elementas a function of relative velocities of the first and secondpressurizing elements and a capacitance correction factor for correctingfor volume expansion of the first and second expandable bodies. Movementof the first and second pressurizing elements may be controlled with analgorithm. The first expandable body may be pressurized to a firstpressure, and the second expandable body may be pressurized to a secondpressure. In one embodiment, the first pressure may be higher than thesecond pressure. The capacitance correction factor may be a function ofthe volume in the first and second expandable bodies, and a pressureinside the first and second expandable bodies. The velocity of the firstpressurizing member may be higher than the velocity of the secondpressurizing member.

In another embodiment, a method for capacitance volume correction in amulti-fluid delivery system may include the steps of pressurizing afirst syringe having a first injection fluid to a first pressure byreducing the volume in the first syringe with movement of a first pistonat a first acceleration and pressurizing a second syringe having asecond injection fluid to the first pressure by reducing the volume inthe second syringe with movement of a second piston at a secondacceleration different from the first acceleration. The acceleration ofthe first piston relative to the acceleration of the second piston maybe a function of a capacitance correction factor for correcting volumeexpansion of the first and second syringes. The capacitance correctionfactor may be a function of the volume in the first and second syringes,and the first pressure.

These and other features and characteristics of the fluid path set witha turbulent mixing chamber, as well as the methods of manufacture andfunctions of the related elements of structures and the combination ofparts and economies of manufacture, will become more apparent uponconsideration of the following description and the appended claims withreference to the accompanying drawings, all of which form a part of thisspecification, wherein like reference numerals designate correspondingparts in the various figures. It is to be expressly understood, however,that the drawings are for the purpose of illustration and descriptiononly and are not intended as a definition of the limits of theinvention. As used in the specification and the claims, the singularform of “a”, “an”, and “the” include plural referents unless the contextclearly dictates otherwise.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a fluid delivery system according to oneembodiment.

FIG. 2 is a perspective view of a fluid delivery system according toanother embodiment.

FIG. 3 is a top perspective view of a fluid path for use in a fluiddelivery system.

FIG. 4 is a top perspective view of a flow mixing device in accordancewith a first embodiment.

FIG. 5 is an exploded perspective view of the flow mixing device shownin FIG. 4.

FIG. 6A is a cross-sectional view of the flow mixing device taken alongline A-A shown in FIG. 4.

FIG. 6B is a cross-sectional view of the flow mixing device taken alongline B-B shown in FIG. 4.

FIG. 6C is a cross-sectional view of the flow mixing device taken alongline C-C shown in FIG. 4

FIG. 7 is an exploded perspective view of a flow mixing device inaccordance with a second embodiment.

FIG. 8A is a cross-sectional view of an assembled flow mixing devicetaken along line A-A shown in FIG. 7.

FIG. 8B is a cross-sectional view of an assembled flow mixing devicetaken along line B-B shown in FIG. 7.

FIG. 8C is a cross-sectional view of an assembled flow mixing devicetaken along line C-C shown in FIG. 7.

FIG. 8D is a cross-sectional view of an assembled flow mixing devicetaken along line D-D shown in FIG. 7.

FIG. 9 is an exploded perspective view of the flow mixing device inaccordance with a third embodiment.

FIG. 10 is a cross-sectional view of an assembled flow mixing devicetaken along line A-A shown in FIG. 9.

FIG. 11 is a cross-sectional view of a flow mixing device in accordancewith a fourth embodiment.

FIG. 12 is a cross-sectional view of a flow mixing device in accordancewith a fifth embodiment.

FIG. 13 is an exploded perspective view of a flow mixing device inaccordance with a sixth embodiment.

FIG. 14 is a cross-sectional view of an assembled flow mixing devicetaken along line A-A shown in FIG. 13.

FIG. 15 is a top perspective view of a flow mixing device in accordancewith a seventh embodiment.

FIG. 16 is an exploded perspective view of the flow mixing device shownin FIG. 15.

FIG. 17A is a cross-sectional view of an assembled flow mixing devicetaken along line A-A shown in FIG. 15.

FIG. 17B is a cross-sectional view of an assembled flow mixing devicetaken along line B-B shown in FIG. 15.

FIG. 17C is a cross-sectional view of an assembled flow mixing devicetaken along line C-C shown in FIG. 15.

FIG. 18A is a cross-sectional view of a flow mixing device in accordancewith an eighth embodiment.

FIG. 18B is a cross-sectional view of the flow mixing device shown inFIG. 18A.

FIG. 18C is a cross-sectional view of the flow mixing device shown inFIG. 18A.

FIG. 19 is an exploded perspective view of a flow mixing device inaccordance with a ninth embodiment.

FIG. 20A is a cross-sectional view of the flow mixing device taken alongline A-A shown in FIG. 19.

FIG. 20B is a cross-sectional view of an assembled flow mixing devicetaken along line B-B shown in FIG. 19.

FIG. 21 is a top perspective view of a flow mixing device in accordancewith a tenth embodiment.

FIG. 22 is an exploded perspective view of the flow mixing device shownin FIG. 21.

FIG. 23 is a cross-sectional view of an assembled flow mixing devicetaken along line A-A shown in FIG. 21.

FIG. 24 is a top perspective view of a flow mixing device in accordancewith an eleventh embodiment.

FIG. 25 is an exploded perspective view of the flow mixing device shownin FIG. 24.

FIG. 26 is a top view of a first portion of the flow mixing device shownin FIG. 25.

FIG. 27 is a top perspective view of a flow mixing device in accordancewith a twelfth embodiment.

FIG. 28A is a cross-sectional view of the flow mixing device taken alongline A-A shown in FIG. 27.

FIG. 28B is a cross-sectional view of the flow mixing device taken alongline B-B shown in FIG. 27.

FIG. 29 is a top perspective view of a flow mixing device in accordancewith a thirteenth embodiment.

FIG. 30 is an exploded perspective view of the flow mixing device shownin FIG. 29.

FIG. 31 is a cross-sectional view of the flow mixing device taken alongline A-A shown in FIG. 29.

FIG. 32 is a graph of capacitance volume relative to injection pressurefor a plurality of fill volumes of first and second injection fluids.

FIG. 33 is a graph of backflow volume relative to injection ratios of afirst injection fluid and a second injection fluid.

FIG. 34 is a graph of backflow volume relative to injection pressure fora single injection profile.

FIG. 35 is a velocity graph of pistons driving first and secondinjection fluids during an injection procedure.

FIG. 36 is a modified velocity graph of pistons driving first and secondinjection fluids during an injection procedure.

FIG. 37 is an enlarged portion of the graph shown in FIG. 36.

FIG. 38 is a graph of backflow volume relative to injection pressure fora plurality of injection profiles.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

For purposes of the description hereinafter, spatial orientation terms,as used, shall relate to the referenced embodiment as it is oriented inthe accompanying drawing figures or otherwise described in the followingdetailed description. However, it is to be understood that theembodiments described hereinafter may assume many alternative variationsand configurations. It is also to be understood that the specificcomponents, devices, and features illustrated in the accompanyingdrawing figures and described herein are simply exemplary and should notbe considered as limiting.

FIG. 1 is a perspective view of a fluid delivery system 100 having aflow mixing device 200 according to one embodiment. The fluid deliverysystem 100 is adapted for delivering fluids to a patient during amedical injection procedure. For example, the fluid delivery system 100may be used during an angiographic procedure to inject contrast solutionand common flushing agents, such as saline, into the body of a patient.An example of such a fluid injection or delivery system is disclosed inU.S. patent application Ser. No. 09/982,518, filed on Oct. 18, 2001, nowissued as U.S. Pat. No. 7,094,216 on Aug. 22, 2006 (hereinafter “the'216 patent”), and assigned to the assignee of the present application,the disclosure of which is incorporated herein by reference in itsentirety. Additional examples of fluid delivery systems are disclosed inthe following references: U.S. patent application Ser. No. 10/825,866,filed on Apr. 16, 2004, now issued U.S. Pat. No. 7,556,619 on Jul. 7,2009 (hereinafter “the '619 patent”); U.S. Pat. No. 8,337,456 toSchriver et al., issued Dec. 25, 2012; U.S. Pat. No. 8,147,464 to Spohnet al., issued Apr. 3, 2012; and, U.S. patent application Ser. No.11/004,670, now published as U.S. 2008/0086087 on Apr. 10, 2008, each ofwhich are assigned to the assignee of the present application and thedisclosures of which are incorporated herein by reference in theirentireties. The flow mixing device 200 is generally adapted to interfacewith one or more components of the fluid delivery system 100 to aid inthe mixing of the fluids, particularly contrast solution and salinesolution in the case of angiographic procedures, to be delivered to thepatient.

The fluid delivery system 100 generally includes a powered fluidinjector 102 that is adapted to support and actuate a syringe 104storing a first injection fluid for injection to a patient during amedical procedure, such as an angiographic procedure. The fluid deliverysystem 100 further includes a second injection fluid that may be mixedwith the first injection fluid prior to being delivered to a patient.The injector 102 is generally used to supply the first and secondinjection fluids under pressure to the fluid path set 108 and,ultimately, the patient. The injector 102 may be controlled by a handcontroller 114 to supply the first and second injection fluids atdiscrete and preselected flow rates based on the physical inputs to thehand controller 114.

The following operational discussion of the flow mixing device 200 willbe with exemplary reference to an angiographic procedure involving thefluid delivery system 100 and how the flow mixing device 200 contributesto the homogeneous mixing of the first injection fluid and the secondinjection fluid from the fluid delivery system 100. In typicalangiographic procedures, the first injection fluid is contrast solutionand the second injection fluid or flushing agent is saline. The contrastsolution typically has higher viscosity and specific gravity compared tosaline. One of ordinary skill in the art will appreciate that, dependingon the medical procedure, various other medical fluids can be used asthe first injection fluid and the second injection fluid.

The injector 102 is operatively associated with a fluid control module106. The fluid control module 106 may be adapted for controlling theoperation of the fluid delivery system 100 by allowing the user tomanually select the injection parameters, or select a pre-definedinjection protocol. Alternatively, this functionality may reside with anexternal control unit or with the powered injector 102. In either case,the fluid control module 106 controls the injection pressure and theratio of the first injection fluid relative to the second injectionfluid. The fluid control module 106 is generally adapted to support afluid path set 108 that is generally adapted to fluidly connect thesyringe 104 to a source of first injection fluid (contrast solution)112. The fluid path set 108 is further connected to a source of secondinjection fluid (saline) 110 which is supplied to the patient via thesame catheter as the contrast solution. The flow mixing device 200 isdisposed within the fluid path set 108 and is adapted for mixing thefluids from the syringe 104 and the source of saline 110. The flow ofthe contrast solution from the syringe 104 and the saline is regulatedby the fluid control module 106 which controls the various valves andflow regulating structures in the fluid path set 108 to regulate thedelivery of contrast solution and saline to the patient based on userselected injection parameters, such as total injection volume and ratioof contrast solution and saline. The fluid path set 108 further connectsthe syringe 104 to a catheter (not shown) which is associated with thepatient for supplying the contrast solution and saline to the patient.

FIG. 2 illustrates an alternative embodiment of fluid delivery system100 a having a powered fluid injector 102 a adapted to interface withtwo syringes 104 a, 104 b which may be fluidly connected to a source offirst injection fluid (not shown) and a source of second injection fluid(not shown) or any two desired medical fluids. Injector 102 a isdesirably at least a dual-syringe injector, wherein two fluid deliverysyringes are oriented in a side-by-side relationship and which areseparately actuated by respective piston elements associated with theinjector 102 a. Fluid path set 108 a may be interfaced with injector 102a in a similar manner to that described previously in connection withfluid delivery system 100 described with reference to FIG. 1. Inparticular, the injector 102 a is operatively associated with a fluidcontrol module 106 a. The fluid control module 106 a is generallyadapted to support a fluid path set 108 a that is generally adapted tofluidly connect to the first syringe 104 a having a first injectionfluid, such a contrast solution. The fluid path set 108 a is furtherconnected to the second syringe 104 b having a second injection fluid,such as saline. The flow mixing device 200 is disposed within the fluidpath set 108 a and is adapted for mixing the fluid flow from the firstand second syringe 104 a, 104 b. The flow of the first injection fluidfrom the first syringe 104 a and the second injection fluid from thesecond syringe 104 b is regulated by a fluid control module 106 a whichcontrols the various valves and flow regulating structures to regulatethe delivery of first and second medical fluids to the patient based onuser selected injection parameters, such as total injection volume andratio of contrast solution and saline. The fluid path set 108 a furtherconnects to a catheter (not shown) which is associated with the patientfor supplying the first and second medical fluids to the patient. Asuitable multi-syringe fluid injector for use with the above-describedsystem is described in U.S. patent application Ser. No. 13/386,765,filed on Jan. 24, 2012, which published as U.S. Patent ApplicationPublication No. 2012/0123257, and is assigned to the assignee of thepresent application, the disclosure of which is incorporated herein byreference in its entirety. Other relevant multi-fluid delivery systemsare found in U.S. patent application Ser. No. 10/159,592, filed on May30, 2002 (published as U.S. 2004/0064041), U.S. patent application Ser.No. 10/722,370, filed Nov. 25, 2003 (published as U.S. 2005/0113754),and International Patent Application No. PCT/US2012/037491, filed on May11, 2012 (published as WO 2012/155035), all of which are assigned to theassignee of the present application, and the disclosures of which areincorporated herein by reference.

In another embodiment, a manually-controlled fluid delivery system (notshown) may be provided. Similar to power-operated fluid delivery systemsdescribed with reference to FIGS. 1-2, a manually-controlled fluiddelivery system may include a first injector adapted to actuate a firstsyringe storing a first injection fluid, such as a contrast medium, forinjection to a patient during a medical procedure. Themanually-controlled fluid delivery system may also include a secondinjector adapted to actuate a second syringe storing a second injectionfluid, such as saline. A fluid path set is provided for delivering andmixing the first injection fluid and the second injection fluid in adesired ratio prior to being delivered to a patient. An exemplarymanually-controlled fluid delivery system is disclosed in U.S. patentapplication Ser. No. 13/755,883, filed Jan. 31, 2013, assigned to theassignee of the present application, the disclosure of which isincorporated herein by reference.

With reference to FIG. 3, fluid path set 108 is shown removed from thefluid delivery system. The fluid path set 108 includes a first fluidline 116 in fluid communication at its proximal end with the source ofthe first injection fluid and a second fluid line 118 in fluidcommunication at its proximal end with the source of the secondinjection fluid. First and second fluid lines 116, 118 act as fluidconduits for delivering the first and second injection fluid,respectively, from the source of each respective fluid. Distal ends ofeach of the first and second fluid lines 116, 118 are in fluidcommunication with the flow mixing device 200. First and secondinjection fluids flow into the mixing device 200 and mix in the mixingdevice 200. In one embodiment, a contrast medium having a high specificgravity is delivered under pressure to the mixing device 200 through thefirst fluid line 116 and a saline solution having a lower specificgravity relative to the contrast medium is delivered under pressure tothe mixing device 200 through the second fluid line 118. Then, the mixedsolution of the first and second injection fluid is passed through athird fluid line 120 in fluid connection at its proximal end with adistal end of the flow mixing device 200. A distal end of the thirdfluid line 120 is desirably connected to a catheter by a connector 122to deliver the mixed solution of the first and second injection fluid tothe patient. The connector 122 may be bonded to the third fluid line 120by a conventional UV bonding technique. Alternatively, the connector 122may be coupled to the third fluid line 120 by an over-molding technique.While FIG. 3 illustrates the connector 122 being provided on the thirdfluid line 120, the connector 122 may be provided on any one or all ofthe first, second, and third fluid lines 116, 118, 120, respectively.One or more valves 124 may be provided within the fluid path set 108 toselectively block the passage of first and/or second injection fluidthrough the fluid path set 108. For example, a one-way valve may beprovided on one or both of the first and second fluid lines 116, 118,respectively, to prevent the first or second injection fluid to flowback into the source of the first and second injection fluid.Alternatively, or in addition, the one-way valve may be provided on thethird fluid line 120 to prevent the mixed solution of the first andsecond injection fluids to flow back into the flow mixing device 200. Inone embodiment, the one or more valves 124 may be provided directly onthe flow mixing device 200.

With reference to FIGS. 4, 5, and 6A-6C, a flow mixing device 200 a isillustrated in accordance with a first embodiment. Flow mixing device200 a includes a housing 202 a having a proximal end 204 a opposite adistal end 205 a. The proximal end 204 a of the housing 202 a includes afirst fluid port 206 a and a second fluid port 208 a (shown in FIG. 6A)which are connected or connectable to respective first fluid line 116and second fluid line 118 (not shown). The proximal end 204 a of thehousing 202 a may include a connector (not shown) for connecting thefirst and second fluid lines 116, 118 to the flow mixing device 200 a.The distal end 205 a of the housing 202 a includes a third fluid port210 a which is connected or connectable to the third fluid line 120. Thedistal end 205 a of the housing 202 a may include a connector (notshown) for connecting the flow mixing device 200 a to the third fluidline 120 or to a catheter.

The housing 202 a of the flow mixing device 200 a defines a mixingchamber 212 a (shown in FIG. 6A) where first and second injection fluidsmix to form a mixed solution. The mixing chamber 212 a is adapted forproviding a homogenous mixing flow under turbulent conditions to promotea thorough mixing of the first and second injection fluids and produce asubstantially homogeneous mixed solution. Additionally, the mixingchamber 212 a is also adapted to eliminate zones of stagnant fluid flow.The housing 202 a is desirably formed from a medical-grade plasticmaterial having sufficient rigidity to prevent any substantial expansionof the housing 202 a during the injection procedure. For example, thehousing 202 a is adapted to retain its shape without appreciableexpansion in volume at an injection pressure of 1200 psi.

With specific reference to FIG. 5, and with continuing reference to FIG.4, the housing 202 a of the flow mixing device 200 a includes a firstportion 214 a and second portion 216 a. The first portion 214 a of thehousing 202 a has a substantially conical proximal end 218 a and asubstantially cylindrical distal end 220 a. A collar 222 a surrounds thebase of the conical proximal end 218 a of the first portion 214 a. Thesecond portion 216 a includes a flange 224 a that corresponds to thecollar 222 a of the first portion 214 a to receive the flange 224 awithin the collar 222 a. In another embodiment, the collar 222 a isprovided on the second portion 216 a, while the flange 224 a is providedon the first portion 214 a of the housing 202 a. In one preferred andnon-limiting embodiment, the first and second portions 214 a, 216 a arepermanently coupled together by gluing, ultrasonic welding, aninterference fit connection, or other mechanical securing arrangement.

With reference to FIGS. 6A-6C, and with continuing reference to FIG. 5,the first and second fluid ports 206 a, 208 a extend through the secondportion 216 a and are in fluid communication with the mixing chamber 212a through first and second fluid orifices 226 a, 228 a, respectively.First and second fluid ports 206 a, 208 a are substantially parallel toeach other. In other embodiments, first and second fluid ports 206 a,208 a may be angled relative a longitudinal axis of flow mixing device200 a such that fluid flow of the first and second injection fluidsconverges or diverges relative to the longitudinal axis. In oneexemplary embodiment, a contrast medium may be supplied through thefirst fluid port 206 a and saline may be supplied through the secondfluid port 208 a. Fluid flowing through the first and second fluid ports206 a, 208 a passes through the first and second fluid orifices 226 a,228 a having a reduced cross-section relative to the first and secondfluid ports 206 a, 208 a. First and second fluid orifices 226 a, 228 ahave equal diameters. In another embodiment, the diameter of the firstfluid orifice 226 a may be larger or smaller relative to the diameter ofthe second fluid orifice 228 a. First and second injection fluids mixwithin the mixing chamber 212 a to form a mixed solution. The mixedsolution is discharged from the mixing chamber 212 a through a thirdfluid orifice 230 a provided at a distal end of the first portion 214 aof the housing 202 a. The third fluid orifice 230 a is in fluidcommunication with the third fluid port 210 a that discharges the mixedfluid from the mixing device 200 a through a fluid conduit (not shown).

As best shown in FIGS. 6A and 6B, the mixing chamber 212 a is definedwithin the interior of the first portion 214 a. The mixing chamber 212 ahas a generally conical shape that narrows from the proximal end 218 ato the distal end 220 a such that a cross-sectional shape of the mixingchamber 212 a is substantially circular (FIG. 6C). Alternatively, thecross-sectional shape of the mixing chamber 212 a may be an ellipse orany other shape formed from a curved line. In another embodiment, themixing chamber 212 a may have a first portion that narrows from theproximal end 218 a to the distal end 220 a and a substantiallycylindrical portion that extends therefrom.

With continuing reference to FIGS. 6A-6C, second portion 216 a includesa fluid flow dispersion device 238 a having a stem 240 a and twodeflection members 242 a, 244 a. The stem 240 a is positioned betweenthe first and second fluid orifices 226 a, 228 a and extends in alongitudinal direction toward the distal end 220 a of the first portion214 a. Deflection members 242 a, 244 a extend radially outward from thestem 240 a. A transitional portion between a longitudinally-extendingstem 240 a and the radially-extending deflection members 242 a, 244 a iscurved to gradually transition the flow of the first and secondinjection fluid from a substantially longitudinal direction to asubstantially radial direction with respect to a central axis of themixing chamber. A radial space 246 a is provided between the terminalend of each deflection member 242 a, 244 a and the sidewall of themixing chamber 212 a. First and second injection fluids are deflected toflow from a substantially longitudinal direction to a substantiallyradial direction by the deflection members 242 a, 244 a and are forcedto flow through the radial space 246 a. The rapid change in the flowdirection of the first and second injection fluids promotes turbulentmixing of the first injection fluid and the second injection fluidwithin the mixing chamber 212 a.

With reference to FIGS. 7-8D, a flow mixing device 200 b is illustratedin accordance with a second embodiment. The housing 202 b of the flowmixing device 200 b is substantially similar to the housing 202 a of theflow mixing device 200 a described above. Reference numerals 200 b-230 bin FIG. 7 are used to illustrate identical components as referencenumerals 200 a-230 a in FIGS. 4-5. As the previous discussion regardingthe flow mixing device 200 a generally shown in FIGS. 4-6C is applicableto the embodiment shown in FIGS. 7-8D, only the relevant differencesbetween these systems are discussed hereinafter.

With specific reference to FIGS. 8A-8D, second portion 216 b includestwo deflection members 242 b, 244 b extending radially outward overfirst and second fluid orifices 228 a, 228 b in mutually opposingdirections. First injection fluid is directed in one radial direction bythe first deflection member 242 b, while the second injection fluid isdirected in the opposite radial direction by the second deflectionmember 244 b. A radial space 246 b is provided between the terminal endof each deflection member 242 b, 244 b and the sidewall of the mixingchamber 212 b. First and second injection fluids are deflected to flowin a substantially radial direction by the deflection members 242 b, 244b in opposite directions and forced to flow through the radial space 246b. The rapid change in the flow direction promotes turbulent mixing ofthe first injection fluid and the second injection fluid within themixing chamber 212 b once the first and second injection fluids arerecombined downstream of the deflection members 242 b, 244 b.

With reference to FIGS. 9-10, a flow mixing device 200 c is illustratedin accordance with a third embodiment. Flow mixing device 200 c includesa housing 202 c having a proximal end 204 c opposite a distal end 205 c.The proximal end 204 c of the housing 202 c includes a first fluid portand a second fluid port which are connected or connectable to respectivefirst fluid line 116 and second fluid line 118. The proximal end 204 cof the housing 202 c may include a connector (not shown) for connectingthe first and second fluid lines 116, 118 to the flow mixing device 200c. The distal end 205 c of the housing 202 c includes a third fluid port210 c which is connected or connectable to the third fluid line 120 (notshown in FIGS. 9-10). The distal end 205 c of the housing 202 c mayinclude a connector (not shown) for connecting the flow mixing device200 c to the third fluid line 120 or to a catheter.

With reference to FIG. 10, the housing 202 c of the flow mixing device200 c includes a first portion 214 c and second portion 216 c. The firstportion 214 c of the housing 202 c has a substantially conical proximalend 218 c and a substantially cylindrical distal end 220 c. A collar 222c surrounds the base of the first portion 214 c. The second portion 216c includes a flange 224 c that corresponds to the collar 222 c of thefirst portion 214 c to receive the flange 224 c within the collar 222 c.In another embodiment, the collar 222 c is provided on the secondportion 216 c, while the flange 224 c is provided on the first portion214 c of the housing 202 c. In one preferred and non-limitingembodiment, the first and second portions 214 c, 216 c are permanentlycoupled together by gluing, ultrasonic welding, an interference fitconnection, or other mechanical securing arrangement.

The housing 202 c of the flow mixing device 200 c defines a mixingchamber 212 c (shown in FIG. 10) where first and second injection fluidsmix to form a mixed solution. The mixing chamber 212 c is adapted forproviding a homogenous mixing flow under turbulent conditions to promotea thorough mixing of the first and second injection fluids to produce asubstantially homogeneous mixed solution.

With continuing reference to FIG. 10, the first and second fluid ports206 c, 208 c extend through the second portion 216 c and are in fluidcommunication with the mixing chamber 212 c through first and secondfluid orifices 226 c, 228 c, respectively. First and second fluid ports206 c, 208 c are substantially parallel to each other. In otherembodiments, first and second fluid ports 206 c, 208 c may be angledrelative a longitudinal axis of flow mixing device 200 c such that fluidflow of the first and second injection fluids converges or divergesrelative to the longitudinal axis. In one exemplary embodiment, acontrast medium may be supplied through the first fluid port 206 c andsaline may be injected through the second fluid port 208 c. Fluidflowing through the first and second fluid ports 206 c, 208 c passesthrough the first and second fluid orifice 226 c, 228 c having a reducedcross-section relative to the first and second fluid ports 206 c, 208 c.First and second fluid orifices 226 c, 228 c have equal diameters. Inanother embodiment, the diameter of the first fluid orifice 226 c may belarger or smaller relative to the diameter of the second fluid orifice228 c. First and second injection fluids mix within the mixing chamber212 c to form a mixed solution. The mixed solution is discharged fromthe mixing chamber 212 c through a third fluid orifice 230 c provided ata distal end of the first portion 214 c of the housing 202 c. The thirdfluid orifice 230 c is in fluid communication with a third fluid port230 c that discharges the mixed fluid from the mixing device 200 cthrough the fluid conduit (not shown).

As best shown in FIG. 10, the mixing chamber 212 c is defined within theinterior of the first portion 214 c. The mixing chamber 212 c has agenerally conical shape that narrows from the proximal end 218 c to thedistal end 220 c, such that a cross-sectional shape of the mixingchamber 212 c is substantially circular. Alternatively, thecross-sectional shape of the mixing chamber 212 c may be an ellipse orany other shape formed from a curved line. In another embodiment, themixing chamber 212 c may have a first portion that narrows from theproximal end 218 c to the distal end 220 c and a substantiallycylindrical portion that extends therefrom.

The second portion 216 c includes a fluid flow dispersion device 238 chaving a central hub 240 c and a turbine wheel 241 c rotatable aroundthe central hub 240 c, as shown more fully in FIG. 9. The central hub240 c is located between the first and second fluid orifices 226 c, 228c and extends in a longitudinal direction toward the distal end 220 c ofthe first portion 214 c. Turbine wheel 241 c is rotatably disposed onthe central hub 240 c and is retained in a longitudinal direction by acap 243 c. Turbine wheel 241 c includes a plurality of rotor blades 245c extending radially outward from a central portion of the turbine wheel241 c. Each rotor blade 245 c is angled with respect to a longitudinalaxis of the mixing chamber 212 c such that first and second injectionfluids exiting from first and second fluid orifices 226 c, 228 c aredeflected in a radial direction. Fluid exiting from the first and secondfluid orifices 226 c, 228 c strikes the rotor blades 245 c and causesthe turbine wheel 241 c to rotate. Rotation of the turbine wheel 241 ccauses a scattering of the first and second fluids within the mixingchamber 212 c to promote a homogenous mixing of the fluids.

With reference to FIG. 11, a flow mixing device 200 d is illustrated inaccordance with a fourth embodiment. The housing 202 d of the flowmixing device 200 d is substantially similar to the housing 202 a of theflow mixing device 200 a described above. Reference numerals 200 d-230 din FIG. 11 are used to illustrate identical components as referencenumerals 200 a-230 a in FIGS. 4-5. As the previous discussion regardingthe flow mixing device 200 a generally shown in FIGS. 4-6C is applicableto the embodiment shown in FIG. 11, only the relevant differencesbetween these systems are discussed hereinafter.

With reference to FIG. 11, the mixing chamber 212 d is defined withinthe interior of the first portion 214 d. The mixing chamber 212 d has agenerally cylindrical shape having a substantially circularcross-section. Alternatively, the cross-sectional shape of the mixingchamber 212 d may be an ellipse or any other shape formed from a curvedline. In another embodiment, the mixing chamber 212 d may have a firstportion that narrows from the proximal end 218 d to the distal end 220 dto define a conical profile.

The mixing chamber 212 d has a plurality of mixing balls 213 d disposedwithin. Each mixing ball 213 d is substantially spherical and has adiameter that is larger than the diameter of the smallest of the first,second, and third fluid orifices 226 d, 228 d, 230 d, respectively, inorder to eliminate blocking of the fluid ports. Desirably, each of theplurality of mixing balls 213 d has a diameter sufficiently large toavoid complete occlusion of the first, second, and third fluid orifices226 d, 228 d, 230 d. As the first and second injection fluids enter themixing chamber 212 d, the mixing balls 213 d are agitated by the fluidflow and move about the mixing chamber 212 d. In an embodiment where thehousing 202 d is transparent, the mixing balls 213 d provide a visualindication of injection and mixing. In a purge cycle, the position ofthe mixing balls 213 d within the mixing chamber 212 d is indicative ofwhether the purge is completed. In a further embodiment, the mixingballs 213 d may provide an audible indication of injection as the mixingballs 213 d bounce off of the walls of the mixing chamber 212 d andproduce noise.

With reference to FIG. 12, a flow mixing device 200 e is illustrated inaccordance with a fifth embodiment. The flow mixing device 200 e issubstantially similar to the flow mixing device 200 d described above.Reference numerals 200 e-230 e in FIG. 12 are used to illustrateidentical components as reference numerals 200 d-230 d in FIG. 11. Asthe previous discussion regarding the flow mixing device 200 d isapplicable to the embodiment shown in FIG. 11, only the relevantdifferences between these systems are discussed hereinafter.

Whereas the flow mixing device 200 d includes a plurality of mixingballs 213 d disposed within the mixing chamber 212 d, the flow mixingdevice 200 e includes a porous filter material filing at least a portionof the mixing chamber 212 e. In particular, an open-cell filter element213 e fills the mixing chamber 212 e and creates a fluid pathrestriction which forces the first and second injection fluids to mixwhile passing through the pores. In one embodiment, the filter element213 e is provided only on one lateral side of the mixing chamber 212 ein order to increase a pressure drop of one of the first or secondinjection fluids.

With reference to FIG. 13, a flow mixing device 200 f is illustrated inaccordance with a sixth embodiment. Flow mixing device 200 f includes ahousing 202 f having a proximal end 204 f opposite a distal end 205 f.The proximal end 204 f of the housing 202 f includes a first fluid port206 f and a second fluid port 208 f which are connected or connectableto respective first fluid line 116 and second fluid line 118. Theproximal end 204 f of the housing 202 f may include a connector (notshown) for connecting the first and second fluid lines 116, 118 to theflow mixing device 200 f. The distal end 205 f of the housing 202 fincludes a third fluid port 210 f which is connected or connectable tothe third fluid line 120. The distal end 205 f of the housing 202 f mayinclude a connector (not shown) for connecting the flow mixing device200 f to the third fluid line 120 or to a catheter.

The housing 202 f of the flow mixing device 200 f defines a mixingchamber 212 f (shown in FIG. 14) where first and second injection fluidsmix to form a mixed solution. The mixing chamber 212 f is adapted forproviding a homogenous mixing flow under turbulent conditions to promotea thorough mixing of the first and second injection fluids to produce asubstantially homogeneous mixed solution. Additionally, the mixingchamber 212 f is also adapted to eliminate zones of stagnant fluid flow.The housing 202 f is desirably formed from a medical-grade plasticmaterial having sufficient rigidity to prevent any substantial expansionof the housing 202 f during the injection procedure. For example, thehousing 202 f is adapted to retain its shape without appreciableexpansion at an injection pressure of 1200 psi.

With reference to FIG. 14, the second portion 216 f includes a firstfluid port 206 f for receiving a first injection fluid through a firstfluid conduit (not shown) and a second fluid port 208 f for receiving asecond injection fluid through a second fluid conduit (not shown). Firstand second fluid ports 206 f, 208 f extend through the second portion216 f and are in fluid communication with the mixing chamber 212 fthrough first and second fluid orifices 226 f, 228 f, respectively.First and second fluid ports 206 f, 208 f are substantially parallel toeach other. In other embodiments, first and second fluid ports 206 f,208 f may be angled relative to a longitudinal axis of flow mixingdevice 200 f such that fluid flow of the first and second injectionfluids converges or diverges relative to the longitudinal axis. In oneexemplary embodiment, a contrast medium may be supplied through thefirst fluid port 206 f and saline may be injected through the secondfluid port 208 f. Fluid flowing through the first and second fluid ports206 f, 208 f passes through the first and second fluid orifices 226 f,228 f having a reduced cross-section relative to the first and secondfluid ports 206 f, 208 f. First and second fluid orifices 226 f, 228 fhave equal diameters. In another embodiment, the diameter of the firstfluid orifice 226 f may be larger or smaller relative to the diameter ofthe second fluid orifice 228 f. First and second injection fluids mixwithin the mixing chamber 212 f to form a mixed solution. The mixedsolution is discharged from the mixing chamber 212 f through a thirdfluid orifice 230 f provided at a distal end of the first portion 214 fof the housing 202 f. The third fluid orifice 230 f is in fluidcommunication with the third fluid port 210 f that discharges the mixedfluid from the mixing device 200 f through a fluid conduit (not shown).

The mixing chamber 212 f is defined within the interior of the firstportion 214 f. The mixing chamber 212 f has a generally conical shapehaving a substantially circular cross-section. Alternatively, thecross-sectional shape of the mixing chamber 212 f may be an ellipse orany other shape formed from a curved line.

As best shown in FIG. 13, a disc 237 f is provided between the firstportion 214 f and the second portion 216 f. The disc 237 f is disposedinside the mixing chamber 212 f between the proximal end 218 f and thedistal end 220 f of the first portion 214 f. The disc 237 f has agenerally circular shape adapted to fit inside the mixing chamber 212 f.Desirably, the disc 237 f is adapted to be fixed inside the mixingchamber 212 f and extend substantially perpendicular to a longitudinalaxis of the mixing chamber 212 f. The disc 237 f includes a plurality ofrecesses 239 f extending radially inward from the outer circumference ofthe disc 237 f. When positioned inside the mixing chamber 212 f, therecesses 239 f define a fluid passage 241 f through which mixed solutioncan pass. Additionally, the disc 237 f includes a central opening 243 fextending through the thickness of the disc 237 f. As is well known fromthe fundamental principles of fluid dynamics, a velocity profile of afluid traveling through a circular conduit has a maximum velocity valueat the center of the conduit and a minimum velocity value at thesidewall of the conduit. A stagnation point exists at the surface of theconduit, where the fluid is brought to rest by the conduit and its localvelocity is zero. In order to modify the velocity profile of the firstand second injection fluids such that they mix inside the mixing chamber212 f to create a mixed solution, disc 237 f restricts the fluid suchthat the fluid flow closest to the sidewall of the mixing chamber 212 fis less restricted than the fluid flow closer to the center of themixing chamber 212 f. The fluid passages 241 f provided around theperimeter of the disc 237 f do not cause a restriction in the fluidwhere fluid flow is at its lowest value, while the body of the disc 237f acts as a barrier to reduce the velocity profile of the fastest movingfluid. The central opening 243 f prevents an excess buildup of backuppressure by allowing fluid to pass therethrough. The fluid obstructioncaused by the disc 237 f causes a turbulent flow downstream of the disc237 f to promote homogeneous mixing of the first and second injectionfluids.

With reference to FIGS. 15-17C, a flow mixing device 200 g isillustrated in accordance with a seventh embodiment. Flow mixing device200 g includes a housing 202 g having a proximal end 204 g opposite adistal end 205 g. The proximal end 204 g of the housing 202 g includes afirst fluid port 206 g and a second fluid port 208 g (shown in FIG. 17B)which are connected or connectable to respective first fluid line 116and second fluid line 118. The proximal end 204 g of the housing 202 gmay include a connector (not shown) for connecting the first and secondfluid lines 116, 118 to the flow mixing device 200 g. The distal end 205g of the housing 202 g includes a third fluid port 210 g which isconnected or connectable to the third fluid line 120. The distal end 205g of the housing 202 g may include a connector (not shown) forconnecting the flow mixing device 200 g to the third fluid line 120 orto a catheter.

The housing 202 g of the flow mixing device 200 g defines a mixingchamber 212 g (shown in FIG. 17B) where first and second injectionfluids mix to form a mixed solution. The mixing chamber 212 g is adaptedfor providing a homogenous mixing flow under turbulent conditions topromote a thorough mixing of the first and second injection fluids toproduce a substantially homogeneous mixed solution. Additionally, themixing chamber 212 g is also adapted to eliminate zones of stagnantfluid flow. The housing 202 g is desirably formed from a medical-gradeplastic material having sufficient rigidity to prevent any substantialexpansion of the housing 202 g during the injection procedure. Forexample, the housing 202 g is adapted to retain its shape withoutappreciable expansion at an injection pressure of 1200 psi.

With specific reference to FIGS. 17A-17C, the second portion 216 gincludes a first fluid port 206 g for receiving a first injection fluidthrough a first fluid conduit (not shown) and a second fluid port 208 gfor receiving a second injection fluid through a second fluid conduit(not shown). First and second fluid ports 206 g, 208 g extend throughthe second portion 216 g and are in fluid communication with the mixingchamber 212 g through first and second fluid orifices 226 g, 228 g,respectively. First and second fluid ports 206 g, 208 g aresubstantially parallel to each other. In other embodiments, first andsecond fluid ports 206 g, 208 g may be angled relative a longitudinalaxis of flow mixing device 200 g such that fluid flow of the first andsecond injection fluids converges or diverges relative to thelongitudinal axis. In one exemplary embodiment, a contrast medium may besupplied through the first fluid port 206 g and saline may be injectedthrough the second fluid port 208 g. Fluid flowing through the first andsecond fluid ports 206 g, 208 g passes through the first and secondfluid orifice 226 g, 228 g having a reduced cross-section relative tothe first and second fluid ports 206 g, 208 g. First and second fluidorifices 226 g, 228 g have approximately equal diameters. In anotherembodiment, the diameter of the first fluid orifice 226 g may be largeror smaller relative to the diameter of the second fluid orifice 228 g.First and second injection fluids mix within the mixing chamber 212 g toform a mixed solution. The mixed solution is discharged from the mixingchamber 212 g through a third fluid orifice 230 g provided at a distalend of the first portion 214 g of the housing 202 g. The third fluidorifice 230 g is in fluid communication with the third fluid port 210 gthat discharges the mixed fluid from the mixing device 200 g through afluid conduit (not shown).

The mixing chamber 212 g is defined within the interior of the firstportion 214 g. The mixing chamber 212 g has a generally cylindricalshape having a substantially circular cross-section. Alternatively, thecross-sectional shape of the mixing chamber 212 g may be an ellipse orany other shape formed from a curved line. The mixing chamber 212 g mayhave a first portion that narrows from the proximal end 218 g to thedistal end 220 g to define a conical profile.

With continuing reference to FIGS. 17A-17C, and referring back to FIG.16, flow mixing device 200 g includes a flow dispersion insert 237 gdisposed between the first portion 214 g and the second portion 216 g.The flow dispersion insert 237 g is adapted for being received within acavity of the first portion 214 g. The flow dispersion insert 237 g hasa substantially tubular structure with two pins 239 g extendinglongitudinally outward from a distal end of a sidewall of the flowdispersion insert 237 g. Each of the pins 239 g is received in acorresponding pin hole 241 g provided on a stop surface 243 g at adistal end of the cavity of the first portion 214 g. Pins 239 g areadapted for engaging the pin holes 241 g to prevent rotation of flowdispersion insert 237 g relative to first portion 214 g of the housing202 g. As best shown in FIG. 17A, the flow dispersion insert 237 gincludes a hydrofoil element 245 g extending across a central portion ofthe interior of the tubular structure of the flow dispersion insert 237g. The hydrofoil element 245 g includes a leading edge 247 g located atthe proximate end and a trailing edge 249 g at the distal end of theflow dispersion insert 237 g. The hydrofoil element 245 g furtherincludes an upper chord 251 g extending between the leading edge 247 dand the trailing edge 249 g, and a lower chord 253 g extending betweenthe leading edge 247 g and the trailing edge 249 g opposite the upperchord 251 g. Upper and lower chords 251 g, 253 g define thecross-sectional profile of the hydrofoil element 245 g and define theflow characteristics of the fluid passing across the hydrofoil element245 g. As is well known from hydrodynamics principles, a convex profileof the upper chord 251 g will cause a fluid stream to accelerate overthe upper surface of the hydrofoil element 245 g, thereby creating acondition of low fluid pressure. On the other hand, a flat or concaveprofile of the lower chord 253 g will cause a fluid stream to decelerateover the lower surface of the hydrofoil element 245 g, thereby creatinga condition of high fluid pressure. As fluid traveling across the upperchord 251 g joins the fluid traveling across the lower chord 253 g atthe trailing edge 249 g, vortices shed off of the trailing edge 249 gresult in turbulent fluid flow distally of the trailing edge 249 g topromote a homogeneous mixing of the first and second injection fluidsinside the mixing chamber 212 g. In the embodiment shown in FIG. 17B,first and second fluid orifices 226 g, 228 g are substantially parallelto the leading edge 247 g of the hydrofoil element 245 g. In anotherembodiment, first and second fluid orifices 226 g, 228 g may be orientedperpendicularly relative to the leading edge 247 g of the hydrofoilelement 245 g.

With reference to FIGS. 18A-18C, a flow mixing device 200 h isillustrated in accordance with an eighth embodiment. The flow mixingdevice 200 h is substantially similar to the flow mixing device 200 gdescribed above. Reference numerals 200 h-230 h in FIGS. 18A-18C areused to illustrate identical components as reference numerals 200 g-230g in FIGS. 15-17C. Whereas the flow mixing device 200 g includes onlyone hydrofoil element 245 g, the flow mixing device 200 h includes aplurality of hydrofoils. In particular, with reference to FIGS. 18A-18C,flow mixing device 200 h includes a flow dispersion insert 237 hdisposed between the first portion 214 h and the second portion 216 h.The flow dispersion insert 237 h is adapted for being received within acavity of the first portion 214 h. The flow dispersion insert 237 h hasa substantially tubular structure with two pins 239 h extendinglongitudinally outward from a distal end of a sidewall of the flowdispersion insert 237 h. Each of the pins 239 h is received in acorresponding pin hole 241 h provided on a stop surface 243 h at adistal end of the cavity of the first portion 214 h. Pins 239 h areadapted for engaging the pin holes 241 h to prevent rotation of flowdispersion insert 237 h relative to first portion 214 h of the housing202 h. As best shown in FIG. 18A, the flow dispersion insert 237 hincludes two hydrofoil elements 245 h, 245 h′ extending across a centralportion of the interior of the tubular structure of the flow dispersioninsert 237 h. The hydrofoil elements 245 h, 245 h′ are offset from eachother such that fluid may pass therebetween. The hydrofoil elements 245h, 245 h′ include a leading edge 247 h, 247 h′ located at the proximateend and a trailing edge 249 h, 249 h′ at the distal end of the flowdispersion insert 237 h. The hydrofoil elements 245 h, 245 h′ furtherinclude an upper chord 251 h, 251 h′ extending between the leading edge247 h, 247 h′ and the trailing edge 249 h, 249 h′, and a lower chord 253h, 253 h′ extending between the leading edge 247 h, 247 h′ and thetrailing edge 249 h, 249 h′ opposite the upper chord 251 h, 251 h′.Upper cords 251 h, 251 h′ and lower chords 253 h, 253 h′ define thecross-sectional profile of the hydrofoil elements 245 h, 245 h′ anddefine the flow characteristics of the fluid passing across thehydrofoil elements 245 h, 245 h′. Hydrofoil elements 245 h, 245 h′ maybe arranged such that (a) the leading edge 247 h of the first hydrofoilelement 245 h is aligned substantially parallel with the leading edge247 h′ of the second hydrofoil element 245 h′, (b) the upper chord 251 hof the first hydrofoil element 245 h is adjacent to the upper chord 251h′ of the second hydrofoil element 245 h′, (c) the lower chord 253 h ofthe first hydrofoil element 245 h is adjacent to the lower chord 253 h′of the second hydrofoil element 245 h′, or (d) the upper chord 251 h ofthe first hydrofoil element is adjacent to the lower chord 253 h′ of thesecond hydrofoil element 245 h′. As is well known from hydrodynamicsprinciples, a convex profile of the upper chord 251 h, 251 h′ will causea fluid stream to accelerate over the upper surface of the hydrofoilelement 245 h, 245 h′, thereby creating a condition of low fluidpressure. On the other hand, a flat or concave profile of the lowerchord 253 h, 253 h′ will cause a fluid stream to decelerate over thelower surface of the hydrofoil element 245 h, 245 h′, thereby creating acondition of high fluid pressure. As fluid traveling across the upperchord 251 h, 251 h′ joins the fluid traveling across the lower chord 253h, 253 h′ at the trailing edge 249 h, 249 h′, vortices shed off of thetrailing edge 249 h, 249 h′ result in turbulent fluid flow distally ofthe trailing edge 249 h, 249 h′ to promote a homogeneous mixing of thefirst and second injection fluids inside the mixing chamber 212 h. Inthe embodiment shown in FIG. 18B, first and second fluid orifices 226 h,228 h are substantially parallel to the leading edges 247 h, 247 h′ ofthe two hydrofoil elements 245 h, 245 h′. In another embodiment, firstand second fluid orifices 226 h, 228 h may be oriented perpendicularlyrelative to the leading edges 247 h, 246 h′ of the two hydrofoilelements 245 h, 245 h′.

With reference to FIGS. 19-20B, a flow mixing device 200 i isillustrated in accordance with a ninth embodiment. Flow mixing device200 i includes a housing 202 i having a proximal end 204 i opposite adistal end 205 i. The proximal end 204 i of the housing 202 i includes afirst fluid port 206 i and a second fluid port 208 i (shown in FIG. 20A)which are connected or connectable to respective first fluid line 116and second fluid line 118. The proximal end 204 i of the housing 202 imay include a connector (not shown) for connecting the first and secondfluid lines 116, 118 to the flow mixing device 200 i. The distal end 205i of the housing 202 i includes a third fluid port 210 i which isconnected or connectable to the third fluid line 120. The distal end 205i of the housing 202 i may include a connector (not shown) forconnecting the flow mixing device 200 i to the third fluid line 120 orto a catheter.

The housing 202 i of the flow mixing device 200 i defines a mixingchamber 212 i (shown in FIG. 20A) where first and second injectionfluids mix to form a mixed solution. The mixing chamber 212 i is adaptedfor providing a homogenous mixing flow under turbulent conditions topromote a thorough mixing of the first and second injection fluids toproduce a substantially homogeneous mixed solution. Additionally, themixing chamber 212 i is also adapted to eliminate zones of stagnantfluid flow. The housing 202 i is desirably formed from a medical-gradeplastic material having sufficient rigidity to prevent any substantialexpansion of the housing 202 i during the injection procedure. Forexample, the housing 202 i is adapted to retain its shape withoutappreciable expansion at an injection pressure of 1200 psi.

With specific reference to FIGS. 20A-20B, the first and second fluidports 206 i, 208 i extend through the second portion 216 i and are influid communication with the mixing chamber 212 i through first andsecond fluid orifices 226 i, 228 i, respectively. First and second fluidports 206 i, 208 i are substantially parallel to each other. In otherembodiments, first and second fluid ports 206 i, 208 i may be angledrelative a longitudinal axis of flow mixing device 200 i such that fluidflow of the first and second injection fluids converges or divergesrelative to the longitudinal axis. In one exemplary embodiment, acontrast medium may be supplied through the first fluid port 206 i andsaline may be injected through the second fluid port 208 i. Fluidflowing through the first and second fluid ports 206 i, 208 i passesthrough the first and second fluid orifice 226 i, 228 i having a reducedcross-section relative to the first and second fluid ports 206 i, 208 i.First and second fluid orifices 226 i, 228 i have equal diameters. Inanother embodiment, the diameter of the first fluid orifice 226 i may belarger or smaller relative to the diameter of the second fluid orifice228 i. First and second injection fluids mix within the mixing chamber212 i to form a mixed solution. The mixed solution is discharged fromthe mixing chamber 212 i through a third fluid orifice 230 i provided ata distal end of the first portion 214 i of the housing 202 i. The thirdfluid orifice 230 i is in fluid communication with the third fluid port210 i that discharges the mixed fluid from the mixing device 200 ithrough a fluid conduit, such as the third fluid line 120 connected to acatheter, as discussed above with reference to FIG. 3.

With reference to FIGS. 19 and 20A, flow mixing device 200 i includes aplurality of flow dispersion inserts 237 i disposed between the firstportion 214 i and the second portion 216 i. The flow dispersion inserts237 i are adapted for being received within a cavity of the firstportion 214 i. The flow dispersion inserts 237 i have a substantiallytubular structure with two pins 239 h extending longitudinally outwardfrom a distal end of a sidewall of the flow dispersion insert 237 i andtwo pin holes 241 i extending into the sidewall of the flow dispersioninsert at the proximal end thereof. Each of the pins 239 i is receivedin the corresponding pin hole 241 i provided on the adjacent flowdispersion insert 237 i. The pins 239 i of the flow dispersion insertclosest to the distal end of the first portion 214 i is received insidea stop surface 243 i at a distal end of the first portion 214 i. Pins239 i are adapted for engaging the pin holes 241 i to prevent rotationof flow dispersion insert 237 i relative to first portion 214 i of thehousing 202 i.

With continuing reference to FIG. 20A, each flow dispersion insert 237 ihas a substantially cylindrical exterior adapted to be received insidethe first portion 214 i. Each flow dispersion insert 237 i furtherincludes a hollow interior. Collectively, the hollow interiors of theplurality of flow dispersion inserts 237 i define the mixing chamber 212i. Each flow dispersion insert includes a plurality of wings 245 i thatextend radially inward from the inside sidewall of the flow dispersioninsert 237 i. The wings 245 i are spaced apart at equal intervals aboutthe inner circumference of the flow dispersion insert 237 i. Forexample, the embodiment illustrated in FIG. 20A includes four wings 245i spaced apart at 90° intervals. Adjacent flow dispersion inserts 237 iare desirably rotated with respect to each other such that wings 245 iof one flow dispersion insert 237 i are angularly offset with regard tothe adjacent flow dispersion insert 237 i. In the embodiment shown inFIG. 20A, the three flow dispersion inserts 237 i are provided, wherethe first and last flow dispersion inserts 237 i are positioned suchthat the wings 245 i on these inserts are in angular alignment withrespect to the longitudinal axis extending through the mixing chamber212 i. The middle flow dispersion insert 237 i is angularly offset withregard to the first and last flow dispersion inserts 237 i such that thewings 245 i on the middle insert are offset with regard to the first andlast flow dispersion inserts 237 i. While FIG. 20A illustrates threeflow dispersion inserts 237 i, one of ordinary skill in the art wouldappreciate that any number of flow dispersion inserts 237 i can beprovided. The wings 245 i in each flow dispersion insert 237 i create anobstruction in the fluid path through the mixing chamber 212 i togenerate a turbulent fluid flow through the mixing chamber 212 i.

With reference to FIGS. 21-23, a flow mixing device 200 j is illustratedin accordance with a tenth embodiment. Flow mixing device 200 j includesa housing 202 j having a proximal end 204 j opposite a distal end 205 j.The distal end 205 j of the housing 202 j may include a connector (notshown) for connecting the flow mixing device 200 j to the third fluidline 120 or to a catheter. The housing 202 j of the flow mixing device200 j defines a mixing chamber 212 j (shown in FIG. 22) where first andsecond injection fluids mix to form a mixed solution. The mixing chamber212 j is adapted for providing a homogenous mixing flow under turbulentconditions to promote a thorough mixing of the first and secondinjection fluids to produce a substantially homogeneous mixed solution.Additionally, the mixing chamber 212 j is also adapted to eliminatezones of stagnant fluid flow. The housing 202 j is desirably formed froma medical-grade plastic material having sufficient rigidity to preventany substantial expansion of the housing 202 j during the injectionprocedure. For example, the housing 202 j is adapted to retain its shapewithout appreciable expansion at an injection pressure of 1200 psi.

With specific reference to FIG. 22, the housing 202 j includes a firstportion 214 j and a second portion 216 j joined together at a seam 217 jextending around the outer perimeter of the lateral sides of the firstand second portions 214 j, 216 j. The seam 217 j defines a seal betweenthe first and second portions 214 j, 216 j to prevent fluid leakage fromthe mixing device 200 j. The seam 217 j includes a groove 219 j providedon one of the first or second portions 214 j, 216 j of the housing 202j, and a corresponding projection 221 j on the other of the first orsecond portions 214 j, 216 j such that the projection 221 j is receivedinside the groove 219 j. The first portion 214 j and the second portion216 j are joined at the seam 217 j by, for example, ultrasonic welding,UV bonding, or other joining techniques.

The housing 202 j includes a first fluid port 206 j for receiving afirst injection fluid through a first fluid conduit (not shown) and asecond fluid port 208 j for receiving a second injection fluid through asecond fluid conduit (not shown). First and second fluid ports 206 j,208 j extend through the first and second portions 214 j, 216 j of thehousing 202 j and are in fluid communication with the mixing chamber 212j through first and second fluid orifices 226 j, 228 j, respectively.First and second fluid ports 206 j, 208 j are substantially parallel toeach other. In other embodiments, first and second fluid ports 206 j,208 j may be angled relative to a longitudinal axis of flow mixingdevice 200 j such that fluid flow of the first and second injectionfluids converges or diverges relative to the longitudinal axis. In oneexemplary embodiment, a contrast medium may be supplied through thefirst fluid port 206 j and saline may be injected through the secondfluid port 208 j. Fluid flowing through the first and second fluid ports206 j, 208 j passes through the first and second fluid orifices 226 j,228 j having a reduced cross-section relative to the first and secondfluid ports 206 j, 208 j. First and second fluid orifices 226 j, 228 jhave equal diameters. In another embodiment, the diameter of the firstfluid orifice 226 j may be larger or smaller relative to the diameter ofthe second fluid orifice 228 j. First and second injection fluids mixwithin the mixing chamber 212 j to form a mixed solution. The mixedsolution is discharged from the mixing chamber 212 j through a thirdfluid orifice 230 j provided at a distal end of the first portion 214 jof the housing 202 j. The third fluid orifice 230 j is in fluidcommunication with the third fluid port 210 j that discharges the mixedfluid from the mixing device 200 j through a fluid conduit (not shown).

With continued reference to FIG. 22, mixing chamber 212 j is defined bytwo sinusoidal fluid paths 213 j extending through the longitudinallength of the mixing chamber 212 j. Each sinusoidal fluid path 213 j issubstantially circular in cross section (FIG. 23). The sinusoidal fluidpaths 213 j intersect at a plurality of intersection points 215 j spacedapart at regular intervals over the longitudinal length of the mixingchamber 212 j. At each intersection point 215 j, fluid flow is combinedfrom the portion of the sinusoidal fluid paths 213 j upstream of theintersection point 215 j and divided prior to continuing downstream ofthe intersection point 215 j. The repeated combining and dividing fluidflow promotes turbulent mixing inside the mixing chamber 212 j toproduce a thoroughly mixed solution of the first and second injectionfluids.

With reference to FIGS. 24-26, a flow mixing device 200 k is illustratedin accordance with an eleventh embodiment. Flow mixing device 200 kincludes a housing 202 k having a proximal end 204 k opposite a distalend 205 k. The proximal end 204 k of the housing 202 k includes a firstfluid port 206 k and a second fluid port 208 k (shown in FIG. 25) whichare connected or connectable to a respective first fluid line 116 andsecond fluid line 118. First injection fluid, such as a contrastsolution, is delivered to the first fluid port 206 k through the firstfluid line 116, while the second injection fluid, such as saline, isdelivered to the second fluid port 208 k. The proximal end 204 k of thehousing 202 k may include a connector (not shown) for connecting thefirst and second fluid lines 116, 118 to the flow mixing device 200 k.The distal end 205 k of the housing 202 k includes a third fluid port210 k which is connected or connectable to the third fluid line 120. Asthe first and second injection fluids are introduced into the housing202 k of the flow mixing device 200 k, they mix to produce a mixedsolution of the first and second injection fluid. This mixed solutionflows through the housing 202 k and exits the flow mixing device 200 kthrough the third fluid port 210 a. The distal end 205 k of the housing202 k may include a connector (not shown) for connecting the flow mixingdevice 200 k to the third fluid line 120 or to a catheter.

The housing 202 k of the flow mixing device 200 k defines a mixingchamber 212 k (shown in FIG. 25) where first and second injection fluidsmix to form a mixed solution. The mixing chamber 212 k is adapted forproviding a homogenous mixing flow under turbulent conditions to promotea thorough mixing of the first and second injection fluids to produce asubstantially homogeneous mixed solution. Additionally, the mixingchamber 212 k is also adapted to eliminate zones of stagnant fluid flow.The housing 202 k is desirably formed from a medical-grade plasticmaterial having sufficient rigidity to prevent any substantial expansionof the housing 202 k during the injection procedure. For example, thehousing 202 k is adapted to retain its shape without appreciableexpansion at an injection pressure of 1200 psi.

With reference to FIGS. 25-26, the housing 202 k includes a firstportion 214 k and a second portion 216 k joined together at a seam 217 kextending around the outer perimeter of the lateral sides of the firstand second portions 214 k, 216 k. The seam 217 k defines a seal betweenthe first and second portions 214 k, 216 k to prevent fluid leakage fromthe mixing device 200 k. The seam 217 k includes a groove 219 k providedon one of the first or second portions 214 k, 216 k of the housing 202k, and a corresponding projection 221 k on the other of the first orsecond portions 214 k, 216 k such that the projection 221 k is receivedinside the groove 219 k.

The housing 202 k includes a first fluid port 206 k for receiving afirst injection fluid through a first fluid conduit (not shown) and asecond fluid port 208 k for receiving a second injection fluid through asecond fluid conduit (not shown). First and second fluid ports 206 k,208 k extend through the first and second portion 214 k, 216 k of thehousing 202 k and are in fluid communication with the mixing chamber 212k through first and second fluid orifices 226 k, 228 k, respectively.First and second fluid ports 206 k, 208 k are substantially parallel toeach other. In other embodiments, first and second fluid ports 206 k,208 k may be angled relative a longitudinal axis of flow mixing device200 k such that fluid flow of the first and second injection fluidsconverges or diverges relative to the longitudinal axis. In oneexemplary embodiment, a contrast medium may be supplied through thefirst fluid port 206 k and saline may be injected through the secondfluid port 208 k. Fluid flowing through the first and second fluid ports206 k, 208 k passes through the first and second fluid orifice 226 k,228 k having a reduced cross-section relative to the first and secondfluid ports 206 k, 208 k. First and second fluid orifices 226 k, 228 khave equal diameters. In another embodiment, the diameter of the firstfluid orifice 226 k may be larger or smaller relative to the diameter ofthe second fluid orifice 228 k. First and second injection fluids mixwithin the mixing chamber 212 k to form a mixed solution. The mixedsolution is discharged from the mixing chamber 212 k through a thirdfluid orifice 230 k provided at a distal end of the first portion 214 kof the housing 202 k. The third fluid orifice 230 k is in fluidcommunication with a third fluid port 210 k that discharges the mixedfluid from the mixing device 200 k through a fluid conduit (not shown).

The mixing chamber 212 k is defined within the interior of the firstportion 214 k. The mixing chamber 212 k has a generally cylindricalshape having a substantially circular cross-section. Alternatively, thecross-sectional shape of the mixing chamber 212 k may be an ellipse orany other shape formed from a curved line. The mixing chamber 212 k mayhave a first portion that narrows from the proximal end 218 k to thedistal end 220 k to define a conical profile.

With continued reference to FIGS. 25-26, first and second fluid orifices226 k, 228 k are in fluid communication with the mixing chamber 212 kthrough first and second arcuate tubes 233 k, 235 k. The first andsecond arcuate tubes 233 k, 235 k are curved radially inward toward alongitudinal axis of the mixing chamber 212 k such that they intersectat a juncture at the proximal end of the mixing chamber 212 k. Due tothe characteristics of the Coanda effect, a fluid jet of first or secondinjection fluid passing through the first and second arcuate tubes 233k, 235 k will be attracted to the nearest surface, i.e., the surfaceclosest to the longitudinal axis of the mixing chamber 212 k. Once thefluid jet of the first injection fluid passes through the first arcuatetube 233 k, the fluid jet will continue to flow in an arcuate mannerwithin the mixing chamber 212 k until it collides with an inner sidewallof the mixing chamber 212 k, after which the fluid jet will be deflectedin an opposite direction, thereby defining a sinusoidal travel path.Similarly, once the fluid jet of the second injection fluid passesthrough the second arcuate tube 235 k, the fluid jet will continue toflow in an arcuate manner within the mixing chamber 212 k until itcollides with an inner sidewall of the mixing chamber 212 k, after whichthe fluid jet will be deflected in an opposite direction, therebydefining a sinusoidal travel path opposite to the travel path of thefirst injection fluid. When the first fluid jet intersects with thesecond fluid jet, turbulent mixing of the first and second injectionfluid occurs due to the difference in a radial velocity component ofeach fluid jet.

With reference to FIG. 27-28B, a flow mixing device 200 l is illustratedin accordance with an eleventh embodiment. Flow mixing device 200 lincludes a housing 202 l having a proximal end 204 l opposite a distalend 205 l. The proximal end 204 l of the housing 202 l may include aconnector (not shown) for connecting the first and second fluid lines116, 118 to the flow mixing device 200 l. The distal end 205 l of thehousing 202 l includes a third fluid port 210 l which is connected orconnectable to the third fluid line 120. As the first and secondinjection fluids are introduced into the housing 202 l of the flowmixing device 200 l, they mix to produce a mixed solution of the firstand second injection fluids. This mixed solution flows through thehousing 202 l and exits the flow mixing device 200 l through the thirdfluid port 210 l. The distal end 205 l of the housing 202 l may includea connector (not shown) for connecting the flow mixing device 200 l tothe third fluid line 120 or to a catheter.

The housing 202 l of the flow mixing device 200 l defines a mixingchamber 212 l (shown in FIG. 28A) where first and second injectionfluids mix to form a mixed solution. The mixing chamber 212 l is adaptedfor providing a homogenous mixing flow under turbulent conditions topromote a thorough mixing of the first and second injection fluids toproduce a substantially homogeneous mixed solution. Additionally, themixing chamber 212 l is also adapted to eliminate zones of stagnantfluid flow. The housing 202 l is desirably formed from a medical-gradeplastic material having sufficient rigidity to prevent any substantialexpansion of the housing 202 l during the injection procedure. Forexample, the housing 202 l is adapted to retain its shape withoutappreciable expansion at an injection pressure of 1200 psi.

As best shown in FIG. 28A, the mixing chamber 212 l includes a pluralityof grooves 2131 around the inner circumference of the mixing chamber 212l. The grooves 2131 extend helically through the longitudinal length ofthe mixing chamber 212 l to define a “gun barrel rifling” shape. Asfirst and second injection fluids are delivered to the mixing chamber212 l, the grooves 2131 promote a swirling flow of the fluids along thelongitudinal length of the mixing chamber 212 l.

With reference to FIGS. 29-30, a flow mixing device 200 m is illustratedin accordance with a thirteenth embodiment. Flow mixing device 200 mincludes a housing 202 m having a proximal end 204 m opposite a distalend 205 m. The proximal end 204 m of the housing 202 m includes a firstfluid port 206 m and a second fluid port 208 m (shown in FIG. 31) whichare connected or connectable to respective first fluid line 116 andsecond fluid line 118. First and second fluid ports 206 m, 208 m aresubstantially parallel to each other. In other embodiments, first andsecond fluid ports 206 m, 208 m may be angled relative to a longitudinalaxis of flow mixing device 200 m such that fluid flow of the first andsecond injection fluids converges or diverges relative to thelongitudinal axis. The proximal end 204 m of the housing 202 m mayinclude a connector (not shown) for connecting the first and secondfluid lines 116, 118 to the flow mixing device 200 m. The distal end 205m of the housing 202 m includes a third fluid port 210 m which isconnected or connectable to the third fluid line 120. The distal end 205m of the housing 202 m may include a connector (not shown) forconnecting the flow mixing device 200 m to the third fluid line 120 orto a catheter.

The housing 202 m of the flow mixing device 200 m defines a mixingchamber 212 m (shown in FIG. 31) where first and second injection fluidsmix to form a mixed solution. The mixing chamber 212 m is adapted forproviding a homogenous mixing flow under turbulent conditions to promotea thorough mixing of the first and second injection fluids to produce asubstantially homogeneous mixed solution. Additionally, the mixingchamber 212 m is also adapted to eliminate zones of stagnant fluid flow.The housing 202 m is desirably formed from a medical-grade plasticmaterial having sufficient rigidity to prevent any substantial expansionof the housing 202 m during the injection procedure. For example, thehousing 202 m is adapted to retain its shape without appreciableexpansion at an injection pressure of 1200 psi.

With reference to FIG. 31, fluid flowing through the first and secondfluid ports 206 m, 208 m passes through the first and second fluidorifice 226 m, 228 m having a reduced cross-section relative to thefirst and second fluid ports 206 m, 208 m. The diameter of the firstfluid orifice 226 m is smaller relative to the diameter of the secondfluid orifice 228 m. During fluid injection, a first injection fluid,such as saline, is passed through the first fluid orifice 226 m. Due toa reduced diameter of the first fluid orifice 226 m relative to thesecond fluid orifice 228 m, the first injection fluid experiences ahigher pressure drop across the first fluid orifice 226 m. The higherrelative pressure drop is also associated with a change in the Reynoldsnumber associated with the first injection fluid flowing through thefirst fluid orifice 226 m and a corresponding transition from laminar toturbulent flow. For example, fluid flow of the first injection fluidprior to entering the first fluid orifice 226 m is associated with aReynolds number lower than 2300 (i.e., laminar flow). After experiencingthe pressure drop caused by the diameter reduction between the firstfluid port 206 m and the first fluid orifice 226 m, the Reynolds numberof the first injection fluid will be higher than 4000 (i.e. turbulentflow). Similarly, fluid flow of the second injection fluid prior toentering the second fluid orifice 228 m is also associated with aReynolds number lower than 2300 (i.e., laminar flow); however, becausethe second injection fluid is not subjected to a high pressure drop dueto the diameter reduction between the second fluid port 208 m and thesecond fluid orifice 228 m, the second injection fluid will maintain alaminar flow after passing through the second fluid orifice 228 m. Anadditional benefit of reducing the diameter of the first fluid orifice226 m relative to the second fluid orifice 228 m offsets any backflow ofthe first injection fluid when injecting a ratio of fluids having morethan 50% of the second injection fluid that is more viscous than thefirst injection fluid. By combining a turbulent flow of a firstinjection fluid and a laminar flow of a second injection fluid in themixing chamber 212 m, the mixing of the two fluids to form a mixedsolution is improved. The mixed solution is discharged from the mixingchamber 212 m through a third fluid orifice 230 m provided at a distalend of the first portion 214 m of the housing 202 m. The third fluidorifice 230 m is in fluid communication with the fluid port 210 m thatdischarges the mixed fluid from the mixing device 200 m through a fluidconduit (not shown).

While embodiments of a fluid path set with a flow mixing device andmethods of operation thereof were provided in the foregoing description,those skilled in the art may make modifications and alterations to theseembodiments without departing from the scope and spirit of theinvention. For example, any of the embodiments of the fluid path setwith a flow mixing device can be adapted to receive a third (or more)injection fluid that is introduced into the mixing chamber of the flowmixing device for mixing with one or both of first and second injectionfluids. Accordingly, the foregoing description is intended to beillustrative rather than restrictive.

Having described the various embodiments of the flow mixing device, amethod of backflow compensation will now be described. In a typicalmulti-fluid injection procedure, an injection fluid, such as a contrastsolution, is delivered from a contrast solution source to the patientusing a powered or manual injector. The injected contrast solution isdelivered to a desired site in a patient's body through a catheterinserted into the patient's body, such as the patient's groin area. Oncethe contrast fluid is delivered to the desired site, that area is imagedusing a conventional imaging technique, such as angiography imagining orscanning. The contrast solution becomes clearly visible against thebackground of the surrounding tissue. However, because the contrastsolution often comprises toxic substances that may be harmful to thepatient if delivered in a high dosage or a high concentration, it isdesirable to reduce contrast dosing to the patient, while maintaining aneffective contrast amount necessary for effective imaging. Bysupplementing the overall contrast solution delivery procedure withsaline, additional hydration of the patient occurs automatically andallows the body to remove the toxicity of the contrast solution. Inaddition to improved patient comfort level and less toxicity,introduction of saline at clinically significant pressures and flowrates also allows higher flow rates to be achieved at lower pressuresettings on the injector.

To enable effective simultaneous flow delivery of first and secondinjection fluids, such as contrast solution and saline, substantiallyequal pressure must be present in each delivery line. In a poweredinjection system described above, it is desirable to actuate the pistonelements substantially simultaneously in simultaneous flow deliveryapplications to equalize the pressure in each line. If the injector isoperated with differential pressure in each delivery line of the fluidpath set, the fluid in the lower pressure line may be stopped orreversed until sufficient pressure is achieved in the lower pressureline to enable flow in a desired direction. This time delay could reducethe usefulness of the image quality. This phenomenon is particularlyevident in situations where contrast is injected at a significantlyhigher ratio relative to saline, such as 80% contrast to 20% salineinjection protocol. The flow reversal is exacerbated at high injectionpressures. In small dosage injections at a high injection pressure, flowreversal effectively stops the delivery of saline such that 100%contrast solution is injected, rather than the desired 80% contrast to20% saline ratio. Similar inaccuracies occur at various other injectionprotocols, including, but not limited to 20% contrast to 80% salineratio.

The above-described situation of flow reversal during powered injectionsat high contrast-to-saline ratio occurs due to injection systemcapacitance. Total system capacitance represents the amount ofsuppressed fluid (i.e., backflow volume) that is captured in theswelling of the injector system components due to pressure. Total systemcapacitance is inherent to each fluid injection system and depends on aplurality of factors, including injector construction, mechanicalproperties of materials used to construct the syringe, piston, pressurejacket surrounding the syringe, fluid lines delivering the contrast andsaline to a flow mixing device, etc. The amount of back or reverse flowincreases when the relative speed difference between the two pistons islarge, the simultaneous fluid flow is through a small restriction, thespeed of the total fluid injection is large, and the viscosity of thefluid is high. The back or reverse flow can prevent different ratios ofsimultaneously delivered fluid from ever occurring in certaininjections, which can be a detriment for all two-syringe type injectorsystems.

In general, capacitance is directly correlative to injection pressureand inversely correlative to volume of contrast and saline in thesyringes. For example, in one embodiment, capacitance during aninjection at 1200 psi with 150 ml of contrast and saline remaining inthe syringes is around 10 ml. In another embodiment, the capacitancevolume can be from about 5 ml to about 9 ml. With reference to the graphshown in FIG. 32, several lines labeled A, B, and C show an increase insystem capacitance relative to an increase in injection pressure atdifferent syringe volumes. Line A, which corresponds to both syringescontaining contrast solution or saline at maximum capacity. Lines B andC show the increase in capacitance with an increase in injectionpressure for syringes having ⅔ and ⅓ of maximum fill volume,respectively.

Capacitance is also a function of the ratio at which the first andsecond injection fluids, such as contrast solution and saline, areinjected. With reference to FIG. 33, an illustration of the relativechange in backflow volume relative to the change in ratio between thecontrast solution and saline is illustrated. At a 50%-50% ratio, wherecontrast solution and saline are injected in equal amounts, backflowvolume is minimized because the capacitance on the contrast solutionside is equal to the capacitance on the saline side of the injectionsystem such that substantially equal pressures are present in eachdelivery line. Backflow may occur in situations where first and secondinjection fluids are delivered through long fluid conduits. However, asthe injection ratio of contrast solution and saline changes, backflowvolume increases corresponding to the increase in the ratio. As shown inFIG. 33, backflow volume is lower for low ratios of contrast solutionand saline (i.e., higher saline concentration) than for high ratios(i.e., higher contrast concentration) due to the contrast solutionhaving a significantly higher viscosity relative to saline.

With reference to FIG. 34, backflow volume is shown as a function ofinjection pressure for an injection protocol having a ratio of 80%contrast solution to 20% saline. Based on the injection pressure,desired fluid ratio cannot be realized at low injection volumes, where100% of the injected fluid will be contrast solution. Even when thesaline syringe is pressurized to a level to overcome the systemcapacitance, the overall fluid ratio is higher than the desired ratio.Typically, the desired ratio is selected by simultaneously activatingthe pistons and controlling the velocity and injection time to dispensethe desired quantity of contrast solution and saline. FIG. 35illustrates a velocity profile of pistons driving the first and secondinjection fluids (contrast solution and saline) for an 80%-20% injectionprotocol. As seen from the figure, velocity for each piston is keptconstant during the injection duration, with the velocity of the pistoninjecting the contrast solution (labeled A) being four times faster thanthe velocity of the piston injecting the saline (labeled B). Theacceleration of each piston from rest to a steady state velocity isidentical.

A solution to the problem of eliminating backflow to compensate forsystem capacitance in a high contrast-to-saline ratio is to control therelative acceleration of the pistons in proportion to the capacitiveswelling that is occurring. Thus, the ratio of simultaneous fluiddelivery can be maintained. The difference in acceleration between thepiston controlling the injection of the contrast solution and the pistoncontrolling the injection of saline is determined by the predictedcapacitance volume of the syringe with the correction factor dominatedprimarily by pressure and the axial position of the syringe plungerwithin the syringe barrel.

With reference to FIGS. 36-37, a velocity profile of pistons driving thefirst and second injection fluids (contrast solution and saline) for an80%-20% injection protocol is shown where the acceleration of the pistondriving the first injection fluid (contrast solution) from rest to asteady velocity is lower than the acceleration of the piston driving thesecond injection fluid (saline). Desirably, acceleration of the pistondriving the second injection fluid is maximized such that the pistonreaches its desired velocity in a least amount of time. The accelerationof the piston driving the first injection fluid is controlled as afunction of relative velocities between the two pistons, theacceleration of the piston driving the second injection fluid, and acorrection factor selected to compensate for the system capacitance. Theacceleration of the piston driving the first injection fluid may becontrolled only during the start of the injection procedure, or duringthe start and end of the injection procedure. The correction factor canbe derived from empirical testing or derived from material and shapecalculations of the fluid delivery set and the fluid injection system.

With reference to FIG. 37, a velocity profile of the two pistonscontrolling the injection of first and second injection fluids (i.e.,contrast solution and saline, respectively) is shown in the initialstage of injection prior to the time when the piston driving the firstinjection fluid reaches steady state velocity (labeled A′). The velocityprofile of the piston driving the second injection fluid is labeled asB′. Injection pressure at fluid paths of first and second injectionfluids leading from the syringes are equalized when the areas under thevelocity profiles A′ and B′ are substantially equal. The area under thecurve for velocity profile A′ can be calculated by the followingequation: U₁=½V₁*t, where V₁ is the velocity of the piston driving thefirst injection fluid and t is time. The area under the curve forvelocity profile B′ can be calculated by the following equation:U₂=V₂*t, where V₂ is the velocity of the piston driving the secondinjection fluid and t is time. The calculation of U₂ does not accountfor any velocity gradient from the start of the injection procedureuntil a steady state velocity is achieved because acceleration of thepiston driving the second injection fluid is maximized such that theinitial slope of velocity profile B′ is essentially vertical. Based onthe above equations, the areas under the velocity profiles A′ and B′ aresubstantially equal at a time when the velocity of the piston drivingthe first injection fluid is equal to twice the velocity of the pistondriving the second injection fluid (i.e., V₁=2*V₂). Because theacceleration of the piston driving the second injection fluid is known(i.e., the maximum acceleration A₂ that the piston can achieve), theacceleration of the piston driving the first injection fluid can becalculated as a function of the velocity ratio between the two pistons.The following equation governs the acceleration value A₁ of the pistondriving the first injection fluid: A₁=A₂/(c*(V₁/V₂)), where c is ascalar correction factor selected to compensate for the systemcapacitance and minimize the backflow volume. As noted above, thecorrection factor c can be derived from empirical testing based on aplurality of different injection pressures and fill volumes of thesyringes containing the first and second injection fluids.Alternatively, the correction factor c can be derived from material andshape calculations of the fluid delivery set and the fluid injectionsystem. The correction factor controls the acceleration A₁ of the pistondriving the first injection fluid in the initial stage of fluidinjection in order to compensate for the system capacitance at a giveninjection pressure and the fill volume of the syringes containing thefirst and second injection fluids. The difference in accelerationbetween the piston controlling the injection of the contrast solutionand the piston controlling the injection of saline is determined by thepredicted capacitance volume of the syringes with the correction factorc dominated primarily by pressure and the fill volume of the syringe.

As shown in FIG. 38, a plurality of backflow volume curves are shown asa function of injection pressure for uncorrected acceleration value forthe piston driving the first injection fluid and a corrected value forcorrection factors c. The correction factor is chosen to minimize oreliminate the backflow volume across all injection pressures for a givenfill volume of the syringes containing the first and second injectionfluids. Minimizing or eliminating the backflow volume ensures that theactual ratio of the first and second injection fluids is maintained atall stages of the injection process.

While several embodiments were provided in the foregoing description,those skilled in the art may make modifications and alterations to theseembodiments without departing from the scope and spirit of theinvention. Accordingly, the foregoing description is intended to beillustrative rather than restrictive. The invention describedhereinabove is defined by the appended claims and all changes to theinvention that fall within the meaning and the range of equivalency ofthe claims are to be embraced within their scope.

The invention claimed is:
 1. A flow mixing device configured for usewithin a fluid path between a fluid injector and a fluid line connectedto a patient, the flow mixing device comprising: a housing having aproximal end opposite a distal end spaced apart along a longitudinalaxis, the housing comprising a first portion and a second portion joinedtogether at a seam extending in a direction along the longitudinal axisaround an outer perimeter of lateral sides of the first portion and thesecond portion; a first fluid port for receiving a first injection fluidand a second fluid port for receiving a second injection fluid; a mixingchamber disposed within the housing between the proximal and distal endsof the housing, the mixing chamber being in fluid communication with thefirst and second fluid ports for mixing the first and second injectionfluids; a third fluid port at the distal end of the housing and in fluidcommunication with the mixing chamber for discharging a mixture of thefirst and second injection fluids; and a turbulent flow inducing memberdisposed within the mixing chamber for promoting turbulent mixing of thefirst and second injection fluids, wherein the seam comprises a grooveprovided on one of the first portion and the second portion of thehousing and a corresponding projection on the other of the first portionand the second portion of the housing such that the projection isreceived within the groove.
 2. The flow mixing device of claim 1,wherein the seam defines a seal between the first portion and the secondportion of the housing to prevent fluid leakage from the mixing chamber.3. The flow mixing device of claim 1, wherein the mixing chamber isadapted to eliminate zones of stagnant fluid flow.
 4. The flow mixingdevice of claim 1, wherein the housing retains its shape withoutappreciable expansion at an injection pressure of 1200 psi.
 5. The flowmixing device of claim 1, wherein the first fluid port and the secondfluid port are angled relative to the longitudinal axis of the flowmixing device so a fluid flow of the first injection fluid and thesecond injection fluid converges or diverges relative to thelongitudinal axis.
 6. The flow mixing device of claim 1, wherein theturbulent flow inducing member comprises two sinusoidal fluid pathsextending through the mixing chamber, and wherein the two sinusoidalfluid paths intersect at a plurality of intersection points within themixing chamber.
 7. The flow mixing device of claim 6, wherein, at eachof the plurality of intersection points, fluid flow is combined fromupstream portions of the two sinusoidal fluid paths and divided prior tocontinuing downstream of each of the intersection points.
 8. The flowmixing device of claim 6, wherein the plurality of intersection pointsare spaced apart at regular intervals over a longitudinal length of themixing chamber.
 9. The flow mixing device of claim 1, wherein theturbulent flow inducing member comprises a first arcuate tube in fluidcommunication with the first fluid port and a second arcuate tube influid communication with the second fluid port, wherein the firstarcuate tube and second arcuate tube are curved radially inward toward acentral axis of the mixing chamber.
 10. The flow mixing device of claim9, wherein the mixing chamber has a cross-section that is circular,elliptical, or shaped to define a curved cross-section.
 11. The flowmixing device of claim 9, wherein the mixing chamber has an interiorportion that narrows from the proximal end to the distal end of thehousing to define a conical profile.
 12. The flow mixing device of claim9, wherein fluid mixing at a juncture between the first and secondarcuate tubes is influenced by a Coanda effect caused by the firstinjection fluid and the second injection fluid flowing through the firstarcuate tube and the second arcuate tube.
 13. A fluid path setcomprising: a first fluid line having a proximal end and a distal end,the proximal end fluidly connectable to a source of a first injectionfluid; a second fluid line having a proximal end and a distal end, theproximal end fluidly connectable to a source of a second injectionfluid; a flow mixing device in fluid communication with the distal endsof the first and second fluid lines at a proximal end of the flow mixingdevice, the flow mixing device comprising: a housing having a proximalend opposite a distal end spaced apart along a longitudinal axis, thehousing comprising a first portion and a second portion joined togetherat a seam extending in a direction along the longitudinal axis around anouter perimeter of lateral sides of the first portion and the secondportion; a first fluid port provided at the proximal end of the housingfor receiving the first injection fluid and a second fluid port providedat the proximal end of the housing for receiving the second injectionfluid; a mixing chamber disposed within the housing between the proximaland distal ends, the mixing chamber being in fluid communication withthe first and second fluid ports for mixing the first and secondinjection fluids; a third fluid port provided at the distal end of thehousing and in fluid communication with the mixing chamber fordischarging a mixture of the first and second injection fluids; and aturbulent flow inducing member disposed within the mixing chamber forpromoting turbulent mixing of the first and second injection fluids; anda third fluid line in fluid communication with the flow mixing device ata distal end of the flow mixing device, wherein the seam comprises agroove provided on one of the first portion and the second portion ofthe housing and a corresponding projection on the other of the firstportion and the second portion of the housing such that the projectionis received within the groove.
 14. The fluid path set of claim 13,wherein the seam defines a seal between the first portion and the secondportion of the housing to prevent fluid leakage from the mixing chamber.15. The fluid path set of claim 13, wherein the turbulent flow inducingmember comprises two sinusoidal fluid paths extending through the mixingchamber, and wherein the two sinusoidal fluid paths intersect at aplurality of intersection points within the mixing chamber.
 16. Thefluid path set of claim 13, wherein the turbulent flow inducing membercomprises a first arcuate tube in fluid communication with the firstfluid port and a second arcuate tube in fluid communication with thesecond fluid port, wherein the first arcuate tube and the second arcuatetube are curved radially inward toward a central axis of the mixingchamber and fluid mixing at a juncture between the first and secondarcuate tubes is influenced by a Coanda effect caused by the firstinjection fluid and the second injection fluid flowing through the firstarcuate tube and the second arcuate tube.
 17. A flow mixing deviceconfigured for use within a fluid path between a fluid injector and afluid line connected to a patient, the flow mixing device comprising: ahousing having a proximal end opposite a distal end spaced apart along alongitudinal axis, the housing comprising a first portion and a secondportion joined together at a seam extending in a direction along thelongitudinal axis around an outer perimeter of lateral sides of thefirst portion and the second portion; a first fluid port provided at theproximal end of the housing for receiving a first injection fluid and asecond fluid port provided at the proximal end of the housing forreceiving a second injection fluid; a mixing chamber disposed within thehousing between the proximal and distal ends, the mixing chamber beingin fluid communication with the first and second fluid ports for mixingthe first and second injection fluids; a third fluid port provided atthe distal end of the housing and in fluid communication with the mixingchamber for discharging a mixture of the first and second injectionfluids; and a turbulent flow inducing member disposed within the mixingchamber for promoting turbulent mixing of the first and second injectionfluids, wherein the seam defines a seal between the first portion andthe second portion of the housing to prevent fluid leakage from themixing chamber, wherein the seam comprises a groove provided on one ofthe first portion and the second portion of the housing and acorresponding projection on the other of the first portion and thesecond portion of the housing such that the projection is receivedwithin the groove to provide the seal, wherein the turbulent flowinducing member comprises two sinusoidal fluid paths extending throughthe mixing chamber, and wherein the two sinusoidal fluid paths intersectat a plurality of intersection points within the mixing chamber.
 18. Thefluid path set of claim 14, wherein the turbulent flow inducing membercomprises two sinusoidal fluid paths extending through the mixingchamber, and wherein the two sinusoidal fluid paths intersect at aplurality of intersection points within the mixing chamber.